Speed governor



Dec. 21 1948.

J. SNADER SPEED GOVERNOR 3 Sheets-Sheet 1 Filed Aug. 25, 1944 Wa I INVENTOR.

'JRZJJWI' I. J. SNAD ER SPEED GOVERNOR Dec. 21, 1948.

s Shee ts-Sheet 2 Filed Aug. 25, 1944 INVENTOR.

r jaJSnczaer I. J. SNADER Dec. 21, 1948.

SPEED GOVERNOR 3 Sheets-Sheet 3 Filed Aug. 25,. 1944 INVENTOR.

Patented Dec. 21, 1948 UNITED STATES PATENT OFFICE Manufacturing Corporation, a

Delaware corporation of Application August 25, 1944, Serial No. 551,152

12' Claims. 1

The present invention relates generally to speed controlling governors. Although possessing many capabilities of use it is designed or adapted for use in connection with an airplane having a controllable pitch propeller and a propeller driving engine, and operates by varying the pitch of the propeller blades to control or govern the engine so that it operates at a predetermined speed.

One object of the invention is to provide a governor of this type which is an improvement upon, and is more efiicient than, previously designed governors of the same general character, including that which is disclosed in, and forms the subject matter or", an application for United States Letters Patent filed by me on December 17, 1943, and serially numbered 514,729, and is characterized by the fact that the operating parts thereof are so arranged, designed and constructed that the governor, when in use or operation, is not so sensitive as to respond to momentary changes in the speed of the engine, such, for example, as those that occur when the engine mlsfires.

Another object of the invention is to provide a governor of the type under consideration which includes novel and simple means for so controlling the engine that the latter in connection with abrupt or pronounced acceleration or deceleration is quickly brought back to its predetermined speed without hunting;

A further object of'the'invention is to provide a governor which effectively and efficiently fulfills its intended purpose and is characterized by the fact that it is in the form of a small or compact self-contained unit and may be manufactured at a lower reasonable cost.

Other objects of the invention and the-various advantages and characteristics of the present governor will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

In the drawings which accompany and form a part of this specification or disclosure and in which like numerals of reference denote corresponding parts throughout the several views:

Figure l is a vertical longitudinal section of 0 a governor embodying the invention;

Figure 2 is an end view of the governor;

Figure 3 is a plan view;.

Figures 4, 5 and 6 are transverse sections taken respectively on the lines 4- 1, 5-.5 and 6-45 of Figure l; and

Figure '7 is a circuit diagram showing the switches which are governor actuated and serve to control theactuating devices of the controllable pitch propeller with, which-the governor is associated.

The governor which is shown in the drawings constitutes the preferred form or embodiment of the invention. It is primarily designed or adapted for use in connection with an airplane (not shown) having a controllable pitch propeller and a propeller driving internal combustion engine (both not shown) and, as hereinafter described, operates by varying the angle of the propeller blades to control or govern the engine so that it runs at a predetermined speed. As its primary or principal parts the governor comprises an elongated housing 5'5, an engine driven shaft iii, a tubular shaft W, a shaft l8, an electric pilot motor iii, an inertia member 26 and an actuating element 2 l.

The housing is is preferably formed of cast metal and embodies a horizontally disposed, substantially cylindrical side wall 22 and an end wall 23' at one end of the side wall. The other end of the side wall is provided with an annular series or" equidistantly spaced, outwardly projecting, integral lugs 25. The end wall 23 of the housing is preferably formed integrally with the adjacent end of the sidewall 22 and defines with said side wall a chamber 25 in which substantially all of the operating parts of the governor are mounted. The upper central portion of the side wall 22 has a circular hole 26' extending transversely therethrough and is provided with an integral, upwardly extending, substantially circular wall H. The latter is of materially greater diameter than the hole 26 and is positioned in concentric relation with the hole. It has a fiat upper end surface and defines a compartment 28'which is closed at the upper end thereof by a cover plate 29. The cover plate fits against the flat upper end of the wall 2'! and is removably secured in place by a plurality of vertically extending stud bolts 3d. The lower ends of the stud bolts fit within internally threaded sleeve-like lugs ti on the outer periphery of the wall El. The upper ends of the bolts extend through holes (not shown) in the cover plate 29 and carry clamp nuts 32. Such nuts, when tightened, serve to clamp the cover plate 29 in place. The portions of the upper ends of the stud bolts that are above the clamp nuts serve as means for maintaining the governor as a whole in its desired operative position with respect to the internal combustion engine that it is designed or adapted to control. The central portion of the cover plate 29 is provided with an integral upwardly extending tubular part 33, the lower end of which communicates with the compartment 28.

The shaft iii extends transversely of the housing it and is iournalled in, and extends through,

a bearing 34 in the upwardly extending tubular part 33 on the central portion of the removable cover plate 2%). The outer end of the shaft it an annular shoulder 44.

is adapted to be connected by a flexible shaft or other coupling (not shown) to one of the driven elements or parts of the engine, such, for example, as the cam shaft, in order that the shaft it is driven conjointly with the engine. The inner end of the shaft projects into the compartment 28.

The tubular shaft l'l extends longitudinally of, and is disposed centrally within, the housing l5 and surrounds and is journalled on the shaft !8. It is held against axial displacement, as hereinafter described, and is driven by the engine driven shaft l6 through the medium of a hydraulic clutch 35, a pair of bevel gears 36 and 31 and planetary gearing 38. The hydraulic clutch 35 is disposed in the compartment 28 and comprises a casing 39 and a driven or out-put shaft as well as operating parts within the casting. The inner or lower end of the engine driven shaft l6 projects into the upper portion of the casing 39 and serves to drive the operating parts within the casing. The out-put shaft ll) projects downwards from the lower portion of the casing 39 and is in axial alignment with the engine driven shaft IS. The hydraulic clutch 35 is of the type or variety that permits free drive or rotation of the engine driven shaft i6 while the operating parts of the governor are at rest. When, however, the governor is operated as hereinafter described, by

starting the pilot motor 19, drive of the clutch out-put shaft 40 takes place and such shaft is driven at the same speed as the engine driven shaft it within predetermined torque limits. When the torque exceeds a predetermined value the oil or other fluid in the housing shears and prevents the abnormally high torque from being transmitted to the out-put shaft 50 with the result that drive of the shaft Gil by the engine driven shaft I6 ceases. The clutch 35 is of standard or conventional construction and is so designed that when the governor is in operation while the shaft H5 is being driven from the engine the out-put shaft it! is driven conjointly with the shaft l6. out-put shaft til projects into the upper central portion of the chamber 25 in the housing [5 and is rotatably supported by way of a ball bearing ll. The latter comprises an outer race ll an inner race ll and an annular series of balls M between the two races. The outer race is connected by a drive fit to the portion of the housing side wall 22 that defines the hole 26. The

inner race N of the ball bearing M is keyed or otherwise fixedly secured to the central portion of the clutch out-put shaft 30. The bevel gear 36 is mounted on the lower end of the out-put shaft MI and is held in fixed relation with the out-put shaft as the result of being clamped against the inner race M of the ball bearing l by a nut 22. It meshes with, and normally serves to drive, the bevel gear 37 which, as shown in Figure 1, surrounds the central portion of the tubular shaft l1 and embodies a body 3'! and a hub 3?. The hub is journalled on, or rotatably mounted about, an enlarged, integral, bearingforming part 53 on the central portion of the tubular shaft ll. The body 37 of the bevel gear 3? together with the hub 37 forms the spider for the planetary gearing 38. The latter comprises a ring gear 38, a pair of planetary pinions 38 and a sun gear 38. The ring gear 38 is secured within the inner periphery of the housing side wall 22 by a drive fit and abuts against The planetary pinions As shown in Figure 1, the

38 are in mesh with the ring gear 38* and are positioned one diametrically opposite the other. They are mounted on a pair of stub shafts and these are connected to diametrically opposite portions of the body 3'! of the bevel gear 37. The sun gear 38 is disposed between and meshes with the planetary pinions 38 and is preferably formed integrally with the tubular shaft ll. Preferably the planetary gearing 38 is located on the side of the bevel gear 37 that faces the open or lug equipped end of the housing side wall 22. When the governor is in operation the tubular shaft H is driven from the engine driven shaft I6 through the medium of the hydraulic clutch 35, the bevel gears 36 and 37 and the planetary gearing 38. Fcrpurposes of the present disclosure it will be assumed that the engine driven shaft I6 is driven in a counterclockwise direction as viewed in Figure 3. Because of the arrangement of the various gears and pinions the tubular shaft ll, when viewed from the end of the housing 15 having the end wall 23, will be driven in a clockwise direction.

The shaft l8 extends longitudinally of, and is centrally disposed in, the governor housing l5 and, as hereinbefore pointed out, serves as a journal for the tubular shaft ll which is driven by the engine driven shaft 56. The end of the shaft l8 that is disposed adjacent the end wall 23 of the housing is provided with a reduced stem l8 and this is journalled in a bearing 46 on the central inner portion of the housing end wall 23. The other end of the shaft l8, i. e., the end that is disposed adjacent the lug equipped end of the housing side wall, embodies an enlargement 18 which has at its outer end a pair of radially extending diametrically opposite arms l8. A collar ll on the shaft !3 coacts with the inner end of the enlargement la to hold the tubular shaft ll against axial displacement relatively to the shaft IS.

The electric pilot motor i9 is located adjacent the lug equipped end of the housing side wall 22 and operates through the medium of planetary gearing &8 to drive the shaft 18. It is a direct current motor and comprises a casing 59 and an armature 50. One end of the motor casing is provided with an outwardly extending annular flange til and this fits against the open end of the housing side wall 22 and is connected thereto by way of bolts 5!. The latter extend through aligned or registering holes in the flange 39 and the lugs 24 on the open end of the housing side wall and serve removably to secure the electric pilot motor 4 9 in place. If desired a synchronous motor may be used instead of the electric pilot motor l9 and the frequency of the alternating current that is supplied thereto may be varied to cause the motor to operate at the desired speed. The armature 50 is rotatably mounted in the casing 49 and is arranged so that the shaft thereof is in axial alignment with the shaft l8. A battery 52 serves to supply current to the pilot motor l9. One side of the battery is connected to one of the terminals of the motor by way of a conductor 53 and the other side of the battery is connected tothe other motor terminal by way of a conductor 5%. The last mentioned conductor is provided with a switch 55 and a rheostat 55. The rheostat serves as a medium for varying or changing the speed of the electric pilot motor l9 when the switch 55 is closed. It is of conventional or standard construction and comprisesa resistance element 56 and a rotary arm 56 The arm is movable over the resistanceele'mentin order that more or less of: said element may becut into or out of the circuit for the pilot motor G9. The armature of the. electric pilot motor is driven in the same direction as the tubular engine driven shaft l'l, i. e., in a clockwise direction as viewed from the end of the governor housing having the end wall 23. When the pilot motor is in operation the governor, as hereinafter described, operates to control the engine so that it runs at a predetermined speed, i. e., a speed which is directly proportional to the speed of the pilot motor. By controlling the speed of the pilot motor through themedium of the rheostat 56 the predetermined speed of the engine as controlled by the governor may be correspondingly varied.

The planetary gearing 43 serves to drive the shaft 18 from the armature of the electric pilot motor ill and comprises a sun gear M a pair of planetary pinions t8 and a ring gear 48. The sun gear $3 is keyed or otherwise fixedly secured to the inner end of the armature shaft of the armature, as shown in Figure l. The planetary pinions 33 mesh with, and are driven by, the sun gear. They are positioned one diametrically opposite the other and are rotatably mounted on stub shafts til which extend lengthwise of the governor housing l5 and are mounted on the outer ends of the arms ill. Such arms together with the enlargement Ni of the shaft 58 con stitute the spider of the planetary gearing 8. The ring gear H8 is fixedly secured within the lug equipped end of the side wall 22. of the governor housing [5 and abuts against an annular shoulder 53. When the pilot motor I9 is in operation it operates through the medium of the planetary gearing 48 to drive the shaft 18 in the same direction as the engine driven tubular shaft H which, heretofore pointed out, is a clockwise direction when the shafts l'i and is are viewed from the end of the governor housing with the end wall 23. The planetary gearing 48 is such that when the engine is operated or running at its predetermined speed as determined by the speed of operation of the motor ill the shaft i8 is driven at the same speed as the tubular engine driven shaft H.

In addition to the parts heretofore described the governor comprises a connection between the shafts ll and I8 which limits relative rotation of the two shafts in either direction. Such connection forms a positive drive between the two shafts after one shaft has been rotated relatively to the other to a predetermined extent and consists of a pair of coacting diametrically I opposite rotary members 59. Such members are positioned adjacent the enlargement it on the shaft l8 and are rotatably supported by way of a pair of stub shafts 60. As shown in Figure 1, the stub shafts 60 are arranged in parallel relation with, and on opposite sides of, the shaft enlargement I8 and are disposed in the housing l5, between the planetary gearing 3B and the planetary gearing 48. The ends of the stub shafts that extend in the direction of the planetary gearing 38 are fixedly connected to the outer ends of a pair of radially extending diametrically opposite arms 6| on the end of the tubular shaft H which is adjacent the electric pilot motor [9. Such arms are preferably formed as integral parts of the tubular shaft ll. The other ends of the stub shafts to, i. e., the ends that project or extend in the direction of the planetary gearing 48, extend through apertures in the central portions of the members 59. Nuts 62 on said other ends-of the stub shaftsfilserve in conjunction with the outer ends of the arms 6| to hold the members seagainst axial displacement with respectto the stub shafts while at the same time they permit the members to rotate freely relatively to the stub shafts. The inner and side portionsof the members 59 are provided with arouate slots 63 through which the inner end of the shaft enlargement l8 extends. As shown in Figure 1,'the inner portions of the members 53 are arranged in lapped or axially offset relation. Preferably the slots 83 extend throughout an arc of approximately 270*. The portions of the members 59 that define the outer side parts of the slots 63 are shaped to define internal teeth to and these teeth mesh with an annular series of longitudinally extendingteeth 65 on the inner end of the enlargement 18 on the motor driven shaft it. The outer portions of the members 55 are provided with large sized enlargements constituting weights t6 and these are positioned midway between. the ends of the arcuate slots 63. When the engine with which the governor is associated is operating or running at its predetermined speed and as a result the shafts I! and i8 revolve at the same speed the weights 6%, in response to the action of centrifugal force, maintain the members 59 in a position wherein the tooth equipped inner end of the shaft enlargement I8 is disposed in the central portions of the arcuate slots 53. Should, however, the engine deviate from. its predetermined speed the tubular engine driven shaft I] either overruns or underruns the shaft l8 and causes the members 59 to, revolve about the stub shafts 60. The members 59 will revolve until the tooth equipped inner end of the shaft enlargement lil strikes againstv or is brought into abutment with the trailing ends of the slots 53. Whenv such tooth equipped end abuts against the trailing ends of the slots the two shafts I! and i8 are connected together for conjoint rotation. When the engine accelerates beyond its predetermined speed the members 59 revolve in a clockwise direction as viewed in Figure 5 until the tooth equipped inner end of the shaft enlargement Ni strikes against the slot ends 63 In the event that the engine decelerates from its predetermined speed the members 5Q revolve in a counter-clockwise direction as viewed in Figure 5 until the tooth equipped inner end of the shaft enlargement l8 strikes againstv the slot ends 63*. It is contemplated that the engine with which the governor is associated will be started before the switch 55 of the circuit for the electric pilot motor H] is closed. In connection with starting of the engine the out-put shaft 40 of the hydraulic clutch 35 and the other parts of the governor remain stationary. As soon as the engine is started and the switch 55 is closed so as to start the motor l9'the shaft I8 is set in motion and operates through the medium of the members 59, the planetary gearing 38, the bevel gear 31 and the bevel gear 36 to revolve the clutch out put shaft 40. As soon as the shaft 40 is brought uptospeed the clutch 35 is energized or rendered operative with the result that the engine driven shaft 6'6" operates through the medium of the clutch, the bevel gears 36 and 31 and the planetary gearing so to drive the tubular shaft ll. As heretofore pointed out, when the engine is driven at its predetermined speed the shafts ll and Ill are driven at the same speed and revolve together, and the weights 66 maintainthe members 5am their normal position wherein the tooth equipped inner end of the shaft enlargement 38 is disposed in the central-portions of the slots 63. Either gradual or abrupt acceleration or deceleration of the engine from its predetermined speed does, however, result in limited overrunning or underrunning of the shaft l'i with respect to the shaft it. Because the weights (it are subjected to centrifugal action and tend to hold the members 59 against rotation they operate to counteract relative rotation of the shafts ii and i8 when the engine momentarily decelerates in connection with misfiring.

The inertia member 28 of the governor is in the form of a disc and has a central circular aperture 61 through which extends loosely the end of the tubular engine driven shaft i! that is disposed adjacent the housing end wall 23. It is formed of any suitable substantially heavy materiai, such as metal, and by reason of the manner in which it is mounted it is slidable axially and rotatably relatively to the shaft Il'. As hereafter pointed out more in detail, the member 28 rotates conjointly with the shaft IT in connection with gradual acceleration and deceleration of the engine but, due to its inertia, underruns the shaft i! in connection with abrupt acceleration of the engine and, due to its momentum overruns the shaft i! in connection with abrupt deceleration of the engine. On the side thereof that faces the housing end wall 23 the inertia member 2E3 is provided with a fixed collariike element 68. This element surounds the adjacent end of the tubular engine driven shaft l! and embodies an external screw thread 89 and an internal screw thread 10. Such screw threads are preferably arranged in the same direction and are right hand screw threads. The internal screw thread H3 is arranged in interfitting or screw thread relation with a right hand male or external screw thread "ii on the tubular engine driven shaft i7. When the inertia member underruns the shaft i i in connection with abrupt acceleration of the engine the member together with the collar-like element 68 is shifted axially toward the housing end wall 23 in View of the action of the screw threads iii and II. When the member 2i) overruns the shaft I? in connection with abrupt or pronounced deceleration of the engine such member together with the element $8 is shifted axially away from the housing end wall 23 in response to the action of the interfitting screw threads 1B and H.

The inertia member 20 is controlled by a pair of diametrically opposite coacting members 12 so that it rotates conjointly with the tubular engine driven shaft H except when such shaft abruptly or pronouncedly accelerates or decelerates in response to abrupt acceleration or deceleration of the engine with respect to its predetermined speed. The members '52 are constructed like, and in a measure operate in the same manner as, the members 59. They are in the form of discs, have central apertures i3 and are positioned on opposite sides of the shaft ii and adjacent the side of the inertia member 28 that faces in the direction of the electric pilot motor [9. Pivot bolts i l extend through the apertures 73 and serve to support the members i2 so that they are rotatable about their centers. Such bolts are arranged in parallel relation with the tubular shaft I7 and also extend through holes 75 in the inertia member 20. The inner ends of the pivot bolts fit within screw threaded sockets F6 in the collarlike element 63 with the result that such element is retained in fixed or rigid relation with the inertia member. The inner and side portions of the members '72 are provided with arcuate slots 3? through which extends the adjacent end of the tubular engine driven shaft l7. As shown in Figure 6, the slots 1'! extend through approximately 270 arcs. The portions of the members l2 that define the outer peripheral parts of the slots 7'! are shaped to form internal teeth '18 which mesh with an annlar series of longitudinally extending teeth F9 on the adjacent end of the shaft H. The members 72 are arranged in lapped or longitudinally offset relation and have at the outer portions thereof integral enlargements constituting weights 8!]. Such weights, in

response to the action of centrifugal force, cause the members 72 to assume a position wherein the teeth 15 are disposed in the central portions of the slots T! when the engine is operating at its predetermined speed or gradually accelerates or decelerates with respect to its predetermined speed. When the engine abruptly accelerates the inertia member 20, due to its inertia, underruns the tubular shaft as hereinbefore pointed out and the members 12 revolve in one direction about the pivot bolts 'I i until certain ends of the slots 7 l are brought into abutment with the teeth '89 at which time the member 2!) is connected for conjoint drive with the shaft 17.1 When the engine with which the governor is associated abruptly or pronouncedly decelerates the inertia member 20, due to its momentum, overruns the shaft l1 and the members 72 revolve in the opposite direction until the other ends of the slots ii are brought into abutment with the teeth 79' at which time the member 26 is again connected for conjoint drive with the shaft ill. Generally speaking, the members i2 cause the inertia member to rotate conjointly with the shaft ll' when the engine is operating at its predetermined speed or gradually accelerates or decelelerates with respect to such speed and permit the member to underrun the shaft I! to a limited extent in connection with abrupt acceleration of the engine and to overrun the shaft H in connection with abrupt deceleration of the engine. As previously pointed out, the inertia member it! is axailly displaced by the screw threads and ii away from the pilot motor it when it underruns the shaft H in connection with abrupt acceleration of the engine and said member is shifted by such threads away from thehousing end wall 23 when it overrun the shaft IT in connection with abrupt deceleration of the engine.

The actuating element 21 is composite in character and comprises a collar 8!, a pair of rods 82 and a bar 83. The collar is disposed between the element 63 and the housing end wall 23 and surrounds the adjacent end of the motor driven shaft i3. It is connected to such end of the shaft l8 by splines 84 in order that it is driven conjointly with the shaft while at the same time it is permitted to slide axiallyrelatively thereto. The inner end of the collar 3i, i. e., the end that faces in the direction of the inertia member 20, is provided with a pair of diametrically opposite arms 85 and these extend outwards, then horizontally and then inwards. The inwardly extending portions of the arms 85 fit within the external screw thread 6d, are designated by the reference numeral 85 and in effect constitute cam followers. The screw thread 69 is so arranged that when the element 68, together with the inertia member 28, overruns the motor driven shaft Hi to av limited extent, due to gradual acceleration of the engine, the collar 8! is shifted to a limited extent towards the housing end wall 23, and when the element 68-, together with the inertia member 2!), underruns the shaft I8 to a limited extent, due to gradual deceleration of the engine, the collar 8| of the actuating element 2! is shifted to a limited extent away from the housin end wall 23. The extent of overrunning and underrunning of the inertia member 20 with respect to the shaft i8 is determined by the slots 63 in the members 59. The screw thread connection consisting of the screw threads 10 and H, i. e., the screw thread connection between the collar-like element 68 and the tubular engine driven shaft l-T coacts with the screw thread 69 and the arm ends 85 in such manner that when the inertia member 20 underruns the shaft 18 to a limited extent due to abrupt acceleration of the engine the collar 8| is shifted towards the housing end wall 23 to a greater extent and when the inertia member overruns the shaft 11 to a limited extent due toabrupt deceleration of the engine the collar iii of the actuating element H is shifted axially to a greater extent away from the housing end wall 23. The extent of overrunning and underrunning of the inertia member 20 with respect to the engine driven shaft ii is determined by the slots Tl in the members 12. The rods 82 of the actuating element 2! are positioned on opposite sides of, and are disposed in parallel relation with, the shafts i and E8. The central portions of the rods 82 extend loosely through holes 86 in the outer portion of the housing end wall 23 in order that the rods are slidable longitudinally of the housing H3. The inner ends of the rods are fixedly connected to a ring 81 which surrounds, and is spaced outwards of, the collar 8|. The rods 82 are connected to the collar 8| by a ball bearing 88 in order that they slide or shift conjointly with the collar 8|. Said ball bearing 88 comprises an outer race 88*, an inner race 88 and an annular series of balls 88 between the two races. The outer race 88 fits within the inner periphery of, and is secured to, the ring 8'! which, as previously pointed out, is fixedly connected to the inner ends of the rods 82. The inner race 88 of the ball bearing 88 fits around the outer periphery of, and isv suitably fixedly secured to, the collar 8|. The bar 83 of the actuating element 2! extends between the outer or exteriorly disposed ends of the rods 82 and has its ends fixedly secured to said ends of the rods. As the result of the fact that the bar 83 is fixedly connected to the rods 82 it moves away from and towards the housing end wall 23 in conformity with outward and inward shift of the collar 8|.

As previously pointed out, the governor is adapted to control or govern the speed of the air plane engine with which it is associated by varying the angle of the propeller blades of the controllable pitch propeller. The controllable pitch propeller which is disclosed in, and forms the subject matter of, an application for United States patent filed by Archibald G. Forsyth on August 12, 1943, Serial No. 498,367, now abandoned, represents one form or type of controllable pitch propeller with which the present governor is designed for use. Such controllable pitch propeller includes in addition to a hub and axially rotatable blades on the hub, pitch change mechanism including a magnetic clutch type device for effecting increase in the pitch of the propeller blades at a slow rate, a magnetic clutch type device for effecting decrease in the pitch of the propeller blades at a slow rate, a magnetic clutch type device for effecting increase in pitch of the propeller blades at a fast rate, and a magnetic clutch type device for effecting decrease in pitch of the propeller blades at a fast rate. Such devices are diagrammatically illustrated in Figure 7 of the drawings and are designated, respectively, by the reference numerals 89, 9!], 9! and 92'. These four devices are controlled, respectively, by normally open push button switches 93, 94, 95 and 96. Such switches are mounted on a bracket structure 91 on the exterior of the housing end wall 23 and, as hereinafter described, are controlled automatically in response to axial shift of the actuating element 2|. The switches 93 and 94 are positioned in straddled relation with one end of the bar 33 and are arranged so that the buttons thereof face or oppose one another and are spaced an extremely small distance from said one end of the bar, as shown in Figure 1. The switch 93 is disposed outwards of the bar and the switch 96 is disposed inwards of the bar. The switches 95 and 96 are positioned in straddled relation with the other end of the bar and are located to one side of the switches 98 nad t l, respectively. They are arranged so that their buttons face one another and are spaced apart a distance greater than the distance between the buttons for the switches 53 and 94. When the governor is in its neutral or non-governing position the bar 83 of the actuating element 2i is disposed midway between the buttons for the switches 93 and 94 and midway betwen the buttons for the switches and 96. The switch 95 is positioned outwards of the bar 84 and the switch 96 is positioned inwards of the bar. Closing of the switch 93 results in closing of the hereinafter described circuit for the device 39 and results in the propeller blades being increased in pitch at a slow rate and the engine correspondingly decreasing in speed. When the actuating element 2| is shifted outwards to a limited extent as the result of the cam arrangement in the form of the screw thread 69 and arm ends 85* being brought into play because of a gradual increase in speed of the engine over the predetermined speed the bar 83 effects closing of the push button switch 93 for the slow rate increase pitch device 89. When the actuating elemerit BI is shifted to a limited extent in the op posite direction, i. e., inwards, as the result of said cam arrangement being brought into play due to the engine gradually decreasing in speed the bar 83 effects closing of the switch 94 for the slow rate decrease pitch device 90. Closing of such switch 94 completes the hereinafter described circuit for the device and results in the propeller blades being decreased in pitch at a slow rate and a corresponding increase in speed of the engine. When the actuating element 2! is shifted outwards to a greater extent in connection with abrupt increase in speed of the engine the bar 83 effects closing of the switch 9.5 for the fast rate increase pitch device 9!. Closing of the switch 95 completes the circuit for the device 9i and results in the propeller blades being increased in pitch at a fast rate. When the actuating element 2! is shifted inwards to a greater extent in connection with abrupt decrease in speed of the engine the bar 83 effects closing of the switch 96 for the fast rate decrease pitch device 92. Closing of theswitch, 96 completes the hereinafter described circuit for the device 92 and results in a fast rate decrease in the pitch of the propeller blades; Due to automatic con trol of the switches by the governor theengine 1 l is governed so that it maintains a predetermined speed corresponding to the speed of drive of the motor driven shaft It.

The circuit for the slow rate decrease pitch switch IDI to one contact of the push button 94,

and a conductor I93 leading from the other contact of the switch 9 5 to the other side of the battery. When the switch 99 is closed, as hereinbefore described, the aforementioned circuit is closed with the result that the device 99 decreases v the pitch of the propellers at a slow rate and causes the engine to accelerate or increase in speed. As the engine accelerates to its predetermined speed the actuating element ZI is automatically shifted to its neutral position, thereby resulting in opening of the switch 99.

The circuit for the slow rate increase pitch device 89 includes the battery 98 and comprises a conductor I99 leading from the conductor 99 to one contact of the push button switch 93, a conductor I95 leading from the other contact of the switch 99 to one contact of a normally closed switch I96, a conductor I0 leading from the other contact of the switch I96 to one terminal of the slow rate increase pitch device 89, and a conductor I98 leading from the other terminal of the device 89 to the conductor I03. When the switch 99 is automatically closed as the result of the engine gradually accelerating or over-speeding the aforementioned circuit is completed with the result that the device 89 causes a slow rate increase in pitch of the propeller blades and the engine decreases in speed. As the engine decreases in speed to its predetermined speed the bar 83 is automatically shifted into its normal or neutral position and the switch 93 opens, thus breaking the circuit for the device 89.

The circuit for the fast rate decrease pitch device 92 comprises a conductor I99 leading from the conductor 99 to one termina1 of the device 92, a conductor I I9 leading from the other ter-- I minal of the device 92 to one contact of the switch 96, and a conductor III leading from the other contact of the switch 96 to the conductor I 93. As shown in Figure 7 the conductor III] includes a solenoid I I2 which is operatively connected to the switch I9I in the circuit for the slow rate decrease pitch device 99 and serves when the circuit for the device 92 is closed as the result of closing of the switch 96, to open the switch IIlI and break the circuit for the device 99. When the switch 96 is closed as the result of the engine abruptly under-speeding or decelerating the circuit through the device 92 is completed with the result that the propeller blades are decreased in pitch at a fast rate. As soon as the engine speeds up to the speed determined by the pilot motor I9 the actuating element 2i will have shifted to its neutral position and the switches 94 and 96 thereby opened, and thus effecting an opening of the circuit for the devices 99 and 92. The solenoid H2 for opening the switch IflI is included in the circuit for the fast rate decrease pitch device .92 as hereinbefore described. Pronounced inward shift of the actuating element 2| in connection with initial abrupt deceleration or under-speeding of the engine causes the bar 83 of the element to close the switch 99 before it closes the switch 96. However, as soon as the switch 98 is closed the 12 circuit for the slow rate decrease pitch device 99 is automatically opened as the result of the action of the solenoid H2 even though the switch 99 is held in its closed position by the bar 83.

The circuit for the fast rate increase pitch device 9i includes the battery98 and comprises a conductor II 3 leading from the conductor 99 to one contact of the switch 95, a conductor I it lead ing from the other contact of the switch 95 to one terminal of the device 9|, and a conductor I I5 leading from the other terminal of the device SI to the conductor I93, The conductor H9 includes a solenoid H6 which is operatively connected to the normally closed switch I96 in the circuit for the slow rate increase pitch device 99 and serves when the circuit for the device 9i is closed, to open the switch I06 and thus break the circuit for the device 89. When the switch 95 is closed as the result of the engine initially abruptly accelerating or over-speeding the circuit for the device Si is closed with the result that such device increases the pitch of the propeller blades at a fast rate. When the speed of the engine is decreased to the predetermined speed as set by the motor I 9 the actuating element 2i will have been automatically shifted to its neutral position, resulting in opening of the switches 93 and 95. The solenoid I I6 is included in the circuit for the device 9I because when the bar 83 is moved outwards in connection with initial abrupt acceleration or over-speeding of the engine the switch 93 is closed before the switch 95 and it is hence necessary to break or open the circuit for the device 89 as soon as the circuit for the device 9| is closed by closing of the switch 95. When the switch 95 is closed the solenoid II6 maintains the normally closed switch I 96 in its open position and hence the circuit for the slow rate increase pitch device 89 is opened even though the switch 95 is closed.

The operation of the governor is as follows:

As heretofore pointed out it is contemplated that the engine with which the governor is asso-- ciated will be started before the electric pilot mothe exception of the engine driven shaft I9, remain stationary or at rest due to the action of the hydraulic clutch 35. After the engine is started and is brought to approximately the desired predetermined speed the switch 55 in the circuit for the motor I9 is closed. Closing of the switch results in drive of the armature 50 of the motor and resultantly causes drive of the shaft I8 through the medium of the planetary gearing 48. Drive 01' rotation of the shaft I8 sets in motion the out-put shaft 49 of the hydraulic clutch in view of the driving connection consisting of the members 99, the shaft I I, the planetary gearing 38 and the bevel gears 31 and 39. As soon as the out-put shaft 49 is set in motion the hydraulic clutch 35 becomes operative with the result that the out-put shaft 49 is connected for conjoint drive by the engine driven shaft I6. As soon as the clutch is operative the shaft I1 is driven from the shaft I6 through the medium of the clutch 35, the bevel gears 36 and 3'! and the planetary gearing 38. When the speed of the engine corre sponds to the speed predetermined by the electric pilot motor I9 the shaft I! and I8 rotate at the same speed and the actuating element 2! assumes its neutral or no governing position wherein its bar 83 is disposed midway between the buttons for the switches 93 and 94 and midway between the buttons for the switches 95 and 96. So long as the speed of the engine corresponds to the assigns speed that is determined by the pilot motor the actuating element remains in its neutral position and the four switches 93, dd, 95 and 96 are open. In the event that the engine gradually increases in speed for any reason whatsoever the shaft El and the collar-like element 68 slowly overrun the shaft iii. The element 68 overruns the shaft 18 because, as heretofore pointed out, it is connected to the inertia member 2%! and the latter, due to the action of the members 72, rotates conjointly with the shaft ll in connection with gradual acceleration of the engine. When the element 88 overruns the shaft It in connection with gradual acceleration of the engine the actuating element (.5 action of the external screw thread 69 and the arm ends 85 and results in the bar 83 closing the switch 83 and resultant actuation of the slow rate pitch device 39. Immediately upon actuation of such device the propeller blades are increased in pitch at a slow rate with the result that the engine slows down or decelerates. As the engine slows down or decelerates to its predetermined speed the members 59, due to the centriiugal action of the weights 6B, rotate back to their normal position wherein the tooth equipped inner end of the enlargement [8 is disposed in the central portions of the slots 63, and resultantly cause the shaft ll reversely to rotate with respect to the motor driven shaft it. Such reverse relative rotation on the part of the shaft ll operates through the medium of the external screw thread ii on the element 68, to shift the actuating element '12! back to its neutral or no governing position. As soon as the actuating element returns to its normal position the switch 93 opens and stops actuation of the slow rate increase pitch device 89. It is contemplated that the actuating element will be shifted to its normal position at the time the engine slows down or dccelerates to its predetermined speed.

In the event that the engine gradually decreases in speed for any reason whatsoever the shaft ll together with the inertia member 20 and the collar-like element 58 underruns the motor driven shaft i8, and the external screw thread 69 and the arm ends 85 coact to shift the actuating element 2i inwards to a limited extent and thus effect closing of the switch 9 1 for the slow rate decrease pitch device 99. Immediately upon actuation of such device 99 as the result of closing of its switch 96 the propeller blades are decreased in pitch at a slow rate with the result that the engine increases in speed until it reaches its predetermined or governed speed. As the engine approaches its predetermined speed the members 59, in response to the action of the weights S6, rotate back to their normal position and cause such reverse rotation of the shaft ll, inertia member 2% and the element 68 relatively to the motor driven shaft It as to result in the screw thread E29 and the arm ends w shifting the actuating element 2i back to its normal position. As soon as the element 2! is shifted back to its normal position the switch 94 opens and effects stoppage of the slow rate decrease pitch device 98. It is contemplated that the device 963 will cease operation immediately upon the engine returning to its predetermined speed.

In the event that the engine should abruptly accelerate as the result of the airplane being placed in a steep or sharp dive the operation of the governor is as follows:

At the initial part of abrupt acceleration of the. engine the inertia member 20 and the collaris shifted outwards to a limited extent by the shaped element 68, due to inertia, underrunto a limited extent the engine driven shaft l1 and cause rotation of the members 12 and theirpivot bolts 14. Due to underrunning of the element 68 withrespect to the engine driven shaft the internal screw thread it coacts with the screw thread H on the shaft H to shift the inertia member and the element 68 outwards to such an extent as to cause closing of the switch $3 for the slow rate. increased pitch device 88. As soon as the inertia member underruns the engine driven shaft H to the extent permitted by the slots T1 in the members I2 the member is connected for conjoint drive with the shaft ll and due to the fact that the shaft ll is overrunning the shaft IS the cam arrangement in the form of the screw thread 59 and the arm ends shifts the actuating element 25 outwards such an additional distance as to effect closing of the switch 535 for the fast rate increase pitch device 9i. As soon as the switch S5 closes the fast rate increase pitch device Bl is set in operation and increases the pitch of the propeller blades at a fast rate. The switch 55 remains closed so long as there is an increase in the rate of acceleration of the engine. As soon as there is no increase in the rate of acceleration of the engine as the result of increase in pitch of the blades at a fast rate the inertia member 20 and the collarhaped element 68 return to their normal or neutral position as a result of the action of the coacting rotary members '52. Return of the inertia member to its neutral position brings into play the cam arrangement in the form of the screw threads It and H and results in the actuating element 2i being shifted back to such an extent as to effect opening of the switch 95. Such limited shiftbacl: of the actuating element is not, however, sufiicient to effect opening of the switch 93 for the slow rate increase pitch device 89. So long as the last mentioned switch is closed the slow rate increase pitch device 89 is effective to increase the pitch of the propeller blades at a slow rate. After the engine reaches its peak of acceleration it starts abrupt- 1y to decelerate. During deceleration of the engine before the engine reaches its pro-determined speed, as set or determined by the electric pilot motor iii, the inertia member 20 and the collar-shaped element 33 due to their momentum overrun the engine driven shaft H and cause the cam arrangement in the form of the screw threads 10 and H to shift the actuating element 2| inwards to its neutral position even though the cam arrangement in the form of the screw thread 69 and the arm ends 85 are effective. After return of the element to its neutral position the engine, due to the momentum of its parts, slows down to its predetermined speed. The point at which the actuating element is returned to its neutral position prior to levelling off of the engine to its predetermined speed depends upon the degree of abruptness of deceleration. If the magnitude or degree of abruptness of deceleration is great then the actuating element 2i will be shifted to its no governing position in connection with deceleration of the engine quite a bit ahead of the engine decelerating to its predetermined speed. If the degree of abruptness of deceleration is comparatively small then the actuating element 2| will bereturned to its neutral position at a point directly in advance of the engine due to its momentum levelling off to its predetermined speed, i. e., the speed determined or fixed by the pilot motor 15. In view of the manner in which the rotary members l2 coact with the governor assumes a no governing position in advance of the engine reaching the predetermined speed after abrupt acceleration and hence the engine will automatically level ofi to its predetermined speed with substantially no hunting. In other words, the arrangement of the governor is such that in connection with pronounced or abrupt accelera tion of the engine for any reason whatsoever the switches for the fast and slow rate increase pitch devices are opened ahead of the time when the engine levels oiT to its predetermined speed, thus compensating for the momentum eifect of the engine which would normally cause the engine to pass its predetermined speed and result in hunting under governor control. The compensating or anticipating feature of the present governor in connection with abrupt acceleration is entirely automatic and self-adjusting, depending upon the magnitude of abrupt acceleration of the engine.

In the event that the engine should abruptly decelerate as the result of the airplane being placed in an extremely high climbing attitude the governer operates in the same manner as it does in connection with abrupt acceleration, 6X- cept that the inertia member 26, the element 68 and the actuating element 2! moves reversely and the fast rate decrease pitch device 92 is brought into play instead of the fast rate increase pitch device 9 I In connection with abrupt deceleration of the engine the governor automatically assumes its no governing or neutral position prior to the engine returning to its predetermined speed. As soon as the governor cuts out or assumes its no governing position the engine, due to the inertia of its parts, levels off or coasts to the predetermined sped and hence hunting of the engine is eliminated in connection with return or the engine to its predetermined speed. i. e., the speed that is governed or controlled by the speed of drive of the pilot motor By increasing or decreasing the speed or the pilot motor it through the medium of the rheostat 56 the engine will be governed so as to run at an increased or decreased predetermined speed. In other words, when it is desired to increase the speed of the engine to any desired R. P. M. the rheostat is adjusted so as to decrease the amount of resistance 56 in the motor circuit. If it is desired to decrease the speed of the engine the pilot motor is slowed down by manipulation of the rheostat so as to increase the amount of resistance in the motor circuit. By adjusting the rheostat the engine will be controlled automatically by the governor so that it operates at any desired predetermined speed.

The herein described governor is highly emcient in operation and effectively and efficiently fulfills its intended purpose. Its design and construction are such that the tendency of the engine, with which the governor is used, to hunt in connection with governor control is reduced to a minimum. In other words, the governor is so designed and arranged that when the engine acceleration or deceleration ceases under governor control the engine will be operating at the desired or predetermined R. P. M. The governor is characterized by the fact that it is essentially simple in. design and hence may be manufactured at a low and reasonable cost. It is essentially in the form of a self-contained unit and is so designed that the parts thereof are not subject to excessive wear.

Whereas the governor has been described as being particularly designed for use in connection with an airplane engine and as controlling the engine through the medium of a controllable pitch propeller it is to be understood that it may be used for other purposes and in other capacities. It is also to be understood that the invention is not to be restricted to the details set forth since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

l. A governor adapted to maintain an engine at a predetermined speed and comprising a rotary member adapted for drive by the engine, a coaxial rotary second member provided with means for driving it at a predetermined speed, a speed'control element, means operative automatically when the first mentioned member is driven at a different speed from the second memher to actuate the element, and an operating connection between the two members adapted to limit relative rotation of said members and also during drive of said members to urge them to rotate conjointly, and embodying pivot means connected to, and disposed eccentrically of, one of the members, means on the other member forming a concentric arcuate series of teeth, and a rotary element having its central portion supported rotatably by said pivot means and including a concentric arcuate series of teeth in mesh with the first mentioned arcuate series of teeth, stop means at the ends of its arcuate series of teeth, and weight means in opposed relation with its arcuate series of teeth.

2. A governor adapted to maintain an engine at a predetermined speed and comprising a rotary member adapted for drive by the engine, a coaxial rotary second member provided with means for driving it at a predetermined constant speed, a speed control element, means operative automatically when the first mentioned member is driven at a different speed from the second member to actuate the speed control element, and an operating connection between the two members adapted to limit relative rotation of said members and also during drive of said members to urge them to rotate conjointly, and embodying pivot means connected to, and disposed eccentrically of, one of the members, concentric gear teeth on the other member and a rotary element having its central. portion supported rotatably by said pivot means and including an arcuate concentric slot around the gear teeth, an arcuate series of teeth along one side of the slot and in mesh with the gear teeth, and a weight diametrically opposite said arcuate series of teeth.

3. A governor adapted to maintain an engine at a predetermined speed and comprising a rotary member adapted for drive by the engine, a coaxial rotary second member provided with means for driving it at a predetermined constant speed, a speed control element, means operative automatically when the first mentioned member is driven at a difierent speed from the second a member due to acceleration or deceleration of the during drive of said members to urge them to rotate conjointly, and embodying a pair of pivots connected to, and positioned on opposite sides of, one of the members, gear teeth on the other me her and a pair of rotary axially offset elements having their central portions supported rotatably by said pivots and each including a concentric arcuate series of teeth in mesh with the gear teeth, stop means at the end of the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth.

4. A governor adapted tomaintain an engine at a predetermined speed and comprising a slidably mounted speed control element, a shaft adapted for drive by the engine, a coaxial second shaft provided with means for driving it at .a predetermined constant speed, an operating connection between the two shafts adapted to limit relative rotation of said shafts and also during drive of said shafts to urge them to rotateconjointly, and embodying pivot means connected to, and .dis posed eccentrically of, one of the shafts, gear teeth on the other shaft, and a rotary element having its central portion supported rotatably on said pivot means and including a concentric .arcuate series of teeth in mesh with the gear teeth, stop means at the ends of the arcuate series of teeth and a weight diametrically opposite said arcuate series of teeth, and means operative when the first mentioned shaft is driven at a different speed from the second shaft due to acceleration or deceleration of the engine from its predetermined speed to slide the element and embodying a collar-like member mounted on, and connected for drive by, said first mentioned shaft and provided with an external screw thread, and a member connected to said .second shaft so that it is driven conjointly therewith while at the same time it is permitted to slide relatively therto, operatively connected to said element and provided with a cam follower type part in engagement with said external. screw thread.

5. A governor adapted to maintain an engine at a predetermined speed andcomprising, a speed control element, a shaft connected for drive by the engine, a coaxial inertia member r-otatably and slidably mounted adjacent the shaft and adapted when slid to actuate the speed control element, a connection between the shaft and the member adapted to cause the member to rotate at the same speed as the shaft when the engine is running at its predetermined speed or gradually accelerates or decelerates from its predetermined speed and also to permit the member to underrun the shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun the shaft to a limited extent in connection with abrupt deceleration of the engine, and including pivot means connected to the member and position-ed eccentrically with respect to the shaft, gear teeth on the shaft, and a rotary element having its central portion supported rotatably by said pivot means and embodying a concentric arcuate series of teeth in mesh with the gear teeth, stop means at the ends of the arcuate series of teeth, and weight means in opposed relation with said arcuate series of teeth, and cam type means between the shaft and the inertia member adapted to slide the member in connection with underor overrunning of the member with respect to the shaft.

6. A governor adapted to maintain an engine at a predetermined speed and comprising, a speed control element, a shaft adapted for drive by the engine, a coaxial inertia member rotatably and slidablymounted adjacent the shaft and adapted when slid to actuate the speed control element, a connection between the shaft and the member adapted ,to cause the member to rotate at the same speed as the shaft when the engine is running at its predetermined speed or gradual- 1y accelerates or decelerates from its predetermined speed and also to permit the member to underrun the shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun the shaft to a limited. extent in connection with abrupt deceleration of the engine, and including a pivot connected to the member and positioned eccentrically with respect to the shaft, gear teeth on the shaft and arotary element having its central portion supported rotatably by said pivot and embodying a concentric ,arcuate slot around the gear teeth, a series of teeth along one side of the solt and in mesh with said gear teeth, and a Weight diametrically opposite the slot, and cam type means extending between the shaft and the inertia member and adapted to slide the latter in connection with underor overrunning thereof relatively to the shaft.

7. A governor adapted to maintain an engine at a predetermined speed and comprising, a speed control element, a shaft adapted for drive by the engine, a coaxial inertia member rotatably and slidably mounted adjacent the shaft and adapted when slid to actuate the speed control element, a connection between the shaft and the member adapted to cause the member to rotate at the same speed as the shaft when the engine is running at its predetermined speed or gradually accelerates or de-celerates from its predetermined speed and also to permit the member to under run the shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun the shaft to a limited extent in connection with abrupt deceleration of the engine, and embodying a pair of diametrically opposite pivots on the member, gear teeth on the shaft, and a pair of rotary axially offset elements having their central portions supported rotatably by said pivots and each including aconcentric arouate series of teeth in mesh with the gear teeth, stop means at the ends of the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, and cam type means between the shaft and the inertia member adapted to slide the latter in connection with underor overrunning thereof with respect to said shaft.

8. A governor adapted to maintain an engine at a predetermined speed and comprising a movably mounted speed control element, a shaft adapted for drive by the engine, a coaxial second shaft provided with means for driving it at a predetermined constant speed, means operative automatically when the first mentioned shaft is driven at a speed different from the second shaft due to gradual variation in the speed of the engine from its predetermined speed to move the control element to a limited extent, an inertia member rotatably and slidably mounted on said first mentioned shaft and operatively connected to the control element so that when it is slid it moves said element to a greater extent, a connection between said first mentioned shaft and the member adapted to cause the member to retate at the same speed as the first mentioned shaft when the engine is running at its predetermined speed or gradually accelerates or decelerates from its predetermined speed and also to permit the member to underrun the first mentioned shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun said first mentioned shaft to a limited 19 extent in connection with abrupt deceleration of the engine, and embodying pivot means connected to the member and positioned eccentrically with respect to the first mentioned shaft, gear teeth on said first mentioned shaft, and a rotary element having its central portion supported rotatably by said pivot means and embodying a concentric arcuate series of teeth in mesh with the gear teeth, stop means at the ends of the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, and means between said first mentioned shaft and the inertia member adapted to slide said member in'connection with underor overrunning of the member with respect to said first mentioned shaft.

9. A governor adapted to maintain an engine at a predetermined speed and comprising a slidably mounted speed control element, an engine driven shaft, a coaxial second shaft provided with means for driving it at a predetermined constant speed, means operative automatically when the engine driven shaft is driven at a speed different from the second shaft due to gradual variation in the speed of the engine from its predetermined speed to slide said control element to a limited extent, an inertia member rotatably and slidably mounted on said engine driven shaft and operatively connected to the control element so that when it is slid it slides said element to a greater extent, a connection between the engine driven shaft and the member adapted to cause the member to rotate at the same speed as the engine driven shaft when the engine is running at its predetermined speed or gradually accelerates or decelerates from its predetermined speed and also to permit the member to under run said engine driven shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun said engine driven shaft to a limited extent in connection with abrupt deceleration of the engine, and embodying a pair of pivots on opposite sides of the member, gear teeth on the engine driven shaft and a pair of at the ends of the arcuate series of teeth, and a,

weight diametrically opposite said arcuate series of teeth, and a screw thread connection between the engine driven shaft and the inertia member adapted to slide the member in connection with underor overrunning thereof relatively to said,

engine driven shaft.

10. A governor adapted to maintan an engine at a predetermined speed and comprising a slidably mounted speed control element, a shaft adapted for drive by the engine, a coaxial second shaft provided with means for driving it at a predetermined constant speed, means operative automatically when the first mentioned shaft is driven at a speed different from the second shaft due to gradual variation in the speed of the engine from its predetermined speed to slide said control element to a limited extent, an operating connection between the two shafts adapted to limit relative rotation of said shafts and also during drive of said shafts to urge them to rotate oonjointly and embodying pivot means connected to, and disposed eccentrically of, the first mentioned shaft, gear teeth on said second shaft, and a rotary element having its central portion supported rotatably by said pivot means and including a concentric arcuate series of teeth in mesh 20 with the .gear teeth, stop means at theendsof the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, an inertia member rotatably and slidably mounted on said first mentioned shaft and operatively connectedto the control element so thatwhen it is slid it slides said element to a greater extent, a connection between said first mentioned shaft and the member adapted to cause the member to rotate at the same speed as the first mentioned shaft when the engine is running at its predetermined speed or gradually accelerates or decelerates from its predetermined speed and also to permit the member to underrun the first mentioned shaft to alimited extent in connection with abrupt acceleration of the engineand to overrun said first mentioned shaft to a limited extent in connection with abrupt deceleration of the engine, and embodying an eccentrically disposed pivot on the member, gear teeth on said first mentioned shaft and a rotary element having its central portion supported rotatably-by said pivot means and embodying an arcuate series of teeth in mesh with the last mentioned gear teeth,

stop means at the ends of the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, and means between said first mentioned shaft and the inertia member adapted to slide said member in connection with underor overrunning of the member with respect to said first mentioned shaft.

11. A governor adapted to maintain an engine at a predetermined speed, and comprising a slidably mounted speed control element, an electric pilot motor, a pair of rotatably mounted coaxial shafts, means for connecting one of the shafts to one of the driven parts of the engine including a hydraulic clutch, a driving connection between the other shaft and the motor, means operative automatically when the engine driven shaft is driven at a different speed from the motor driven shaft due to gradual acceleration or deceleration of the engine to shift the control element to said limited extent, an operating connection between the two shafts adapted to limit relative rotation of said shafts and also during drive of said shafts to urge them to rotate conjointly, and embodying a pair of pivots connected to, and positioned on opposite sides of, the engine drivenshaft, gear teeth on the motor driven shaft, and a pair of rotary axially offset elements having their central portions rotatably supported on said pivots and each including a concentric arcuate series of teeth in mesh with the gear teeth, stop means at the ends of the arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, an inertia member rotatably and slidably mounted on the engine driven shaft and oper-' atively connected to the control element so that in response to slide thereof it slides the, element to a greater extent, a connection between the engine driven shaft and the member adapted to cause the member to rotate at the same speed as the engine driven shaft when the engine is running at its predetermined speed or. gradually accelerates or decelerates from its predetermined speed and also to permit the member to underrun the shaft to a limited extent in connection with abrupt acceleration of the engine and to overrun said first mentioned shaft to a limited extent in connection with abrupt deceleration of the engine, and embodying a pair of diametrically opposite pivots on the inertia member, gear teeth on the engine driven shaft, and a pair of ,.rotary axially ofiset elements having their central portions sup- 21 ported rotatably on the last mentioned pivots and each including a concentric arcuate series of teeth in mesh With the last mentioned gear teeth, stop means at the ends of the last mentioned arcuate series of teeth, and a weight diametrically opposite said arcuate series of teeth, and a screw thread connection between the engine driven shaft and the inertia member adapted to slide the member in connection with underor overrunning thereof relatively to said engine driven shaft.

12. A governor adapted for use with a prime mover and comprising a rotary member adapted to be driven by the prime mover, a second rotary member provided with means for driving it at a 15 predetermined speed, a speed control element, means operative upon relative rotation of said rotary members to actuate said element, and an operating connection between the two members arranged and designed to limit relative rotation of said members and operative during drive of said members and in response to centrifugal action to urge the members to rotate conjointly.

IRA J. SNADER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 40,754 Humphreys Dec. 1, 1862 158,300 Muchin Dec. 29, 1874 233,734 Crane Oct. 26, 1880 644,983 Keats Mar. 6, 1900 1,167,583 Mehl Jan. 11, 1916 1,936,566 Davenport Nov. 21, 1933 1,946,484 Coupland Feb. 13, 1934 FOREIGN PATENTS 20 Number Country Date 430 Great Britain Feb. 21, 1861 

